title: Nonconvulsive seizures after subarachnoid hemorrhage: Multimodal detection and outcomes.
abstract: OBJECTIVE
  Seizures have been implicated as a cause of secondary brain injury, but the systemic and cerebral physiologic effects of seizures after acute brain injury are poorly understood.
  
  
  METHODS
  We analyzed intracortical electroencephalographic (EEG) and multimodality physiological recordings in 48 comatose subarachnoid hemorrhage patients to better characterize the physiological response to seizures after acute brain injury.
  
  
  RESULTS
  Intracortical seizures were seen in 38% of patients, and 8% had surface seizures. Intracortical seizures were accompanied by elevated heart rate (p = 0.001), blood pressure (p < 0.001), and respiratory rate (p < 0.001). There were trends for rising cerebral perfusion pressure (p = 0.03) and intracranial pressure (p = 0.06) seen after seizure onset. Intracortical seizure-associated increases in global brain metabolism, partial brain tissue oxygenation, and regional cerebral blood flow (rCBF) did not reach significance, but a trend for a pronounced delayed rCBF rise was seen for surface seizures (p = 0.08). Functional outcome was very poor for patients with severe background attenuation without seizures and best for those without severe attenuation or seizures (77% vs 0% dead or severely disabled, respectively). Outcome was intermediate for those with seizures independent of the background EEG and worse for those with intracortical only seizures when compared to those with intracortical and scalp seizures (50% and 25% death or severe disability, respectively).
  
  
  CONCLUSIONS
  We replicated in humans complex physiologic processes associated with seizures after acute brain injury previously described in laboratory experiments and illustrated differences such as the delayed increase in rCBF. These real world physiologic observations may permit more successful translation of laboratory research to the bedside.
authors.affiliation: Division of Critical Care Neurology, Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY; Comprehensive Epilepsy Center, Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY; Department of Neurosurgery, College of Physicians and Surgeons, Columbia University, New York, NY.
authors.forename: Jan
authors.initials: J
authors.lastname: Claassen
authors.forename: Adler
authors.initials: A
authors.lastname: Perotte
authors.forename: David
authors.initials: D
authors.lastname: Albers
authors.forename: Samantha
authors.initials: S
authors.lastname: Kleinberg
authors.forename: J Michael
authors.initials: JM
authors.lastname: Schmidt
authors.forename: Bin
authors.initials: B
authors.lastname: Tu
authors.forename: Neeraj
authors.initials: N
authors.lastname: Badjatia
authors.forename: Hector
authors.initials: H
authors.lastname: Lantigua
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Hirsch
authors.forename: Stephan A
authors.initials: SA
authors.lastname: Mayer
authors.forename: E Sander
authors.initials: ES
authors.lastname: Connolly
authors.forename: George
authors.initials: G
authors.lastname: Hripcsak
mesh_terms: D000368:Aged; D004569:Electroencephalography; D004829:Epilepsy, Generalized / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000150:complications*